spinal chordomas (40 patients) was 66%, and 100% in 19 patients without major surgical stabilization; local control was significantly increased in the non-surgically stabilized vs. surgically stabilized patients (p = 0.003)

3-yr local control for meningioma was 92%

4-yr local control for soft tissue sarcoma was 74%

280 patients have greater than 2 years of follow-up

high grade toxicity was 6% in the skull base and 5% in the paraspinal location.

51 pediatric patients were treated between 2004-2007, including primarily CNS and STS.

Local control is 86% with a median follow-up of 29 months.

All pediatric patients are enrolled in late effects/QOL of study.

Author's Conclusions

The safety and efficacy of spot scanning proton therapy at PSI has been demonstrated across various anatomic sites and tumor types.

The future challenge of spot scanning proton therapy will be the expansion to other tumor types including left-sided breast cancer, and tumors with motion such as lung cancer.

Scientific Implications

The single institution experience of spot scanning proton therapy at PSI across various, but limited, tumor sites is encouraging.

The reduction in local control observed among surgically stabilized spinal chordomas requires further investigation and may be due to such factors as inherent tumor biology, nonrandomized patient selection, and/or range uncertainty and unfavorable dose distributions due to hardware artifacts.

Increased incorporation of spot scanning and continued long-term data on local control and treatment morbidity are needed.